Combination compass and ellipsograph



Aug. 19, 1952 v, DE

COMBINATION COMPASS AND ELLIPSOGRAPH 2 SHEETS-SHEET 1 Filed May 31, 1946 Aug. 19, 1952 v. DEBS 2,607,118

COMBINATION COMPASS AND ELLIPSOGRAPH Filed May 51, 1946 2 SHEETS-SHEET 2 =3 5 V/ifor Bebs V /fO/ney Patented Aug. 19, 1952 COMBINATION COMPASS AND ELLIPSOGRAPH Victor Debs, New York, N. Y.

Application May 31, 1946, Serial No. 673,331

In Great Britain July 27, 1945 1v My invention relatesgenerally to a combination instrument. for precisely drawing and scribing circular, ovoid, elliptical and spiral figures, curves or arcs of varying diameters and shapes, and an object of the invention is to provide a simple and practical instrument of this character which can be readily and accurately adjusted, and which will scribe substantially fluent and mathematically correct lines and figures.

Another important object of my invention is to provide a mechanically superior instrument of the characterindicated which can beconstructed in a durable form'. 1

Other important objects of my invention are to provide a mechanically superior device of the character indicated which will remain in a pre determined adjusted position until re-adjusted; to provide an instrument of the character indicated which is readily and easily operable and adjustable, so that it may be efficient in use; and

to provide an instrument of the character described which may with facility and convenience be used interchangeably as an ellipsograph, compass, ovoid scriber and/or divider.

Other important objects of my invention will be apparent from a reading of the following description in connection with the drawings, wherein for purposes ofillustration I have shown the preferred embodiments of my invention, it being understood that the invention is not limited to such forms, Y but may be embodied in other forms. I I

It is also to be understood that in and by the claims. following the description, it is desired to cover the invention in "whatsoever form it may be embodied.

In the drawings-'- I Figure 1 is a front'elevational view showing in full lines the instrument in an operative position, and showing in broken lines the legs of the instrument in retracted'position.

Figure 2 is a side elevation of Figure 1.

Figure 3 is a sectional view taken through Figure 1 approximately on the line 33.

Figure 4 is a sectional view'taken through Figure 1 approximately on the line 4-4.

Figure 5 is a top plan view showing diagrammatically an adjusted operative position of the instrument and showing the instrument scribing an ellipse, said viewbeing taken through Figure 1 approximately on the line 5 5,

6 Claims. (01. 33-27) Figure 6 is a front elevational view of an auxiliary scriber or cutter of the instrument, showing'in full lines the separable cap, and showing in broken lines said cap affixed to said scriber unit.

Figure? is a side elevational view of the scriber shown in Figure'fi.

Figure 8 is a front elevational view of an alternative embodiment of my invention showing in full lines the instrument in an operative position. and showing in broken lines one of the legs, and part-of another leg, in another operative position.

Figure 9 is a sectional view. taken through Figure 8 approximately on'the line 99.

Figure 10 is a front elevation of an alternative construction of the severable divider or compass member of the instrument.

Figure 11 is a'front elevation showing in full lines an alternative construction of the combination compass and ellipsograph in combination with the divider or compass member shown in Figure 10, in an operative position, and showing in broken lines a part of two of the legs thereof in another operative position.

Figure 12 is a side elevation of an alternative construction of an ink scriber adaptable for'the compass member shown in Figure 10.

Figure 13 is a section taken through Figure 14 approximately on the line l3l3.

Figure 14 is a side elevation of the upper part of the instrument showing in 'detail the upper part of one construction of the S-shaped spreader or expansion spring arm of the instrument.

Figure 15 is a sideelevation of an auxiliary pin point unit adaptable for scribing ovals'and other curvilinear figures.

Figure16 is a front elevation of Figure 15.

Figures 1'7 and 18 are views of a further auxiliary unit.

Referring in detail to the drawings, the numeral I designates the axial stem having a fingerpiece or cap 2. Said stem carries a cylindrical sleeve 3 having a knurled thumb nut 4 to facilitate rotating said sleeve, which is frictionally secured to and rotatable with relation to said tubular stem. r

A depending lug or fork 5 is affixed to said axial stem at the lower end thereof, and the axial or divider legs 6 and 1 are movablysecured between the arms of said depending lug, at a point near the respective upper ends of said axial or divider legs, by means of the concealed pivot 8 at the point of pivot or fulcrum of the said axial or divider legs. The pins 9 and H! are positioned on the said axial or divider legs 6 and 1 respectively, at points proximate to and equidistant from the concealed pivot 8. Connecting links or straightening devices H and I2 retain the axial or divider legs 6 and l at equal angles from the vertical, said connecting links or straightening devices comprising arcuate arms pivotally secured to each other at their ends, said pivot being slidably disposed within the inner face channels !3 of the depending lug 5, the other ends of which are secured by the pins 9 and It respectively.

An adjusting screw M for retaining the said axial or divider legs at a predetermined position is affixed to the throat of the depending lug 5, between the point of pivot or fulcrum of the axial or divider legs and the lower extremity of the depending lug.

The axial or divider legs ii and l are superposed at the fulcrum formed by the concealed pivot 8 between the arms of the depending lug 5 in the manner well known in the art, as shown in Figure 1. Recesses l5 and are provided in the outer faces of the divider legs 6 and 1 respectively to permit clearance of the setting and winding pins of the auxiliary leg hereinafter described when scribing relatively small arcs or ellipses, as shown in broken lines in Figure 1.

By means of set screws H and iii, the pinpoint units [9 and are pivotally secured to the tongued lower ends of the axial or divider legs 6 and 1 respectively.

The pin point units l8 and 29 comprise surface engaging points 2| and 22 respectively, having annular channels 23 and 2.4 respectively (or eyelets, rollers, or other equivalents, which are not shown), which engage and retain the cord hereinafter described, and bores 25 and 26 within which the said points 21 and 22 respectively are removably frictionally secured, or tightly retained by means of set screws 25a and 2611. respectively, as shown in Figure 8,

A bracketcollar 2? is clamped to the cylindrical sleeve 3 by means of a screw 28 on the face of said bracket, so'that said bracket collar may freely move vertically along the length of the said cylindrical sleeve, within the limits set by the knurled thumb nut 4 and an annular ring 29 on the lower end of said cylindrical sleeve. An S-shaped spreader or expansion spring arm 30 is afiixed to the side of the bracket collar 21 by m a s o screws 3 l, or by means of a thumb nut 12, or other similar means, at the upper end thereof, and said spreader depends from said bracket collar to form the third leg of the instrument.

The scriber unit 33 may be made integrally with the spreader or expansion spring arm 30. Preferably, a depending lug 32 links the said spreader to the scriber unit 33. The upper end of said depending lug 32 is rigidly secured to the lower end of said spreader, as by rivets 34, and the lower tongued end of said depending lug 32 holds the said scriber unit, so as to permit alignment of the latter as hereinafter described.

Said scriber unit 33 comprises a shank 35, which may be of any desired cross-section, having an elbow 36 at the upper end which is pivotally secured at the upper end of said elbow between the arms of the depending lug 32. by means of a pin 31 and thumb nut 38, said shank having a bore 39, of any desired cross-section, to carry the scriber hereinafter described, and having a depending arm 49 to carry the cord hereinafter described. A Winding pin 4| for regulating the length of the cord hereinafter described is affixed to an arm 42 on the shank 35 below and adjacent the thumb nut 38, the head of said winding pin preferably being disposed on the side of the shank opposite the thumb nut 38 to facilitate manual manipulation. As shown in Figure 4, the winding pin 4| may be provided with a split shank 42a to prevent slipping of said cord when the instrument is used.

The ink scriber 42b is arcuate in shape, so that the surface contacting point 43 thereof will touch the surface upon which thearc is to be scribed at a point in vertical alignment with the cord aperture or eye 44 of the depending arm i0. Said ink scriber is provided with the usual pin 45 for adjusting the breadth of the point, and thereby regulating the width of the line scribed, and has a shank 46 frictionally engaged in the bore 33 to secure stability and prevent pivoting, and is fitted with a removable friction engaged cap ll to facilitate manipulation. Uniformly heavy contact of the scriber with the surface may be effected by the weight of the cap 41, by provision of a spring exerting downward pressure on the shank 46, or by other similar means. I

A cord 28 of relatively inextensible material such as catgut, silk or wire is aflixed in such a manner that a loop running from the .eye 44 on the depending arm 40 .is formed around the pin point units 2| and 22, on the points 23 and 2 3, which loop can be varied in size by adjustment of the winding pin. For example, said cord may be wound around the winding pin 4|, passed through the eye 49 on the depending arm an, thence through the cord aperture .or eye 44, and thence around the surface engaging points 2! and 22 of the legs 6 and l, at the level of the channelled sections 23 and 24 thereof, to the eye 44 of the depending arm 40, at which point said cord is secured.

When it is desired to use the device to draw an elliptical fi ure having the major axis A-A and the minor axis B- -B the distance from the point ,A or A to the centre C is measured. The pi points 2| and 22 of the legs 6 and 1 respectively are then placed upon the surface upon which the elliptical figure is to be drawn at points X and X on the major axis, which points are the distance A-C' or A -C from the point B or B In thus setting the legs 6 and I, the in point units should be aligned vertically to the surface upon which the elliptical figure is to be drawn, by means of the set screws H and I8. The points are so held in place by slight downward pressure on the finger piece or cap 2. With the .scriber point adjusted so that it intersects the major axis at the point .A or A and makes proper contact with the surface upon which the elliptical figure is to be drawn by setting the bracket rigidly upon the cylindrical sleeve by means of the screw 28. The thumb nutt is then rotated, thereby moving the scribing unit away from its initial alignment with the leg points. The result of this action, it will be seen, is to cause a spreading and consequent shortening of the cord loop, until the element has been moved ninety degrees, or to the bottom of the ellipse (the minor axis B -.B after which the loop again elongates. as the element moves through the next ninetydegrees. It will also be seen that the area of the ellipse is determined entirely by the length of cord loop employed, adjustment of which is made at the winding pin 4i, and that the length-of the ellipse in proper tionto its height or width is determinedby the spacing of the divider leg points and the scriber unit. Thus, an ellipse of any proportionate dimensions may be described, and its size is only limited by the size of the instrument.

It will be seen that the spring 30 keeps the looped cord 48 always taut,as it constantly presses the scriber unit outwardly,-within the limits of outward movement prescribed by the varying lengths of the loop or cord during the scribing of the ellipse. Further, the'loop or cord, by reason of the outward pressure exerted by the spring, will be retained in position in the channelled sections 23 and 24 of the pin point units Band 20 respectively during the scribing of the ellipse. And the weight of the scriber, or a spring or other means (not shown) will'keep the point 43 thereof in contact with the surface upon which the elliptical figure is being drawn. In addition, by means of pressure on the cap 41, further pressure of the scriber'on the surface may be exerted, or the scriber may be lifted off the surface so as to scribe intermittent elliptical arcs.

The recesses l and I5 in the legs 6 and I respectively permit the scribing of very small ellipses, without interference by said legs with the movement of the scriber element around the said legspsuch construction permitting clearance of the said legs by the thumbnut 38 and the winding pin 4 I, as shown in broken lines in Figure 1.

Alternatively, the scriber may be in the form of a divider, cutter, or pencil scribing unit 50, having pin 5|, shank 52, and cap 53, as shown in Figures 6 and '7. Such divider or pencil, of course, in the preferred embodiment, is so constructed as to provide minimal clearance of the depending arm 40, so that the surface contacting point thereof will touch the surface at a point in vertical alignment with the cord aperture or eye 44. r f

In lieu of manual adjustment of the pin point units l9 and 20 to dispose said pin point units vertical to the surface upon which the elliptical figure is to be drawn, spacer members 54 and55 may be employed. Said spacer members, compriseshanks, preferably rectangular in cross section, placed in pivotal relation with the pin point units [9 and 20 by means of pivot pins 55 whereby the lower end of said shanks may rotate on the axis of the pivot pin 56, the upper end of said shanks being in superposed relation between the arms of the depending lug 5 and lying within the slotted recess thereof, as shown in Figure-8. The spacer members 54 and 55 are pivoted at their upper ends to the fork 5. Thus, when the divider legs 6 and I are retracted, or expanded as shown in dotted lines in Figure 8, the pin point units l9 and 20 will remain vertical to the surface upon which the arc is being scribed. Y a

When it is desired to use the device to draw a circle, the pin point 2 l or 22 of the divider leg 6 or *1 is removed, or the said pin point unit is pivoted inwardly on the fulcrum of the set screw l8 of the divider leg 1 until the pin point thereof lies above the plane of the pin point Zlof the divider leg 6 and the scriber point 43. The radius of the circle to be drawn is then set by increasing or decreasing the distance between the pin point 2| of the divider leg 6 and the scriber point 43 by turning the winding pin 32 and thereby increasing or decreasing the length of the loop formed by the cord 48. It will be seen, however, that the alternative construction hereinafter described is preferable for the drawing of circles.

As an alternative construction'of the instrument, and to facilitate the dual use thereof, the

construction shown in Figures {10;and '11 maybe employed. a

In lieu of, the divider, legs[hereinbefore.de:

scribed, the-fork'arms 51.and;58,'.shown.in Figure 10 and constructed in the mannerwell known in the art, may be aflixed to or, constructedlintegrally with the axial stem I., Legs 59 and '60 are pivotally secured to the fork arm's, 5l'and- 58 respectively by pins 6| at theup'per. ends thereof. .Said legs 59 and 60 are provided with elbows 32 and .63 on their outer side faces near their respective upper ends, each elbowhaving a threaded bore 64 to retain the bar hereinafter describedr Saidlegs 59 and 60 are also provided'with recesses? and 66 respectively on their inner side faces near the upper ends, to permit the scribing of relatively small ellipses, by permitting the. said legs to assume a substantially adjacent. operative position. The said legs 59 and 50 are furtherprovided with recesses 61 and 68 respectively which may be of any desired shape which will permitrotation of the -scriber point hereinafter described substantially adjacent said legs, therebyafiording a maximum range for the instrument. I f

Pin point units, and. markingor scribing-units, as hereinbefore. described, vareprovided for the legs 59 and 60., I l

A threaded bar 69 liesbe'tweemthe legs v5,9.and 60, and runs through the threaded-bores I i4,,so that, when rotatedby its. rigidly fiafl'i'xe'cl .central winding disc I0 the said legs will heifetract'ed or expanded an equal horizontaldistance, and will at all times be equidistantfl lfdm'the vertically retained axis stem 1.1 I I The alternative construction of the instrument shown in Figures '1'0 1' and l'l may, as. an equivalent of the screws: 3l ,f retai'n' itsoutwardly arcuate spring arm 'll .by-ineansof a pmn, to facilitate attachment or removal of the third leg, formed by said. spring arm. In'such alternative construction, the depending lug 12a is outwardly arcuate, to aiford clearance for the bar 69 when the legs 59 and 60" are inretracted position.

The scriber unit and inextensible cord are attached in the manner hereinbefore described, ex,- cept that the pin 52aand'cap .53 .thereof. are somewhat shorter, so as to Ibedisposed below the level of the bar, and-permit; operation of the instrument. v 1 Y a Figure 14 shows the slotted'construction of the arcuate spring arm! I whicl'iis welljknown in the art. In order to scribe. ovals, .:the auxiliary unit shown in Figures 15 and 16 may be employed. Said unit comprises a shank 13fand legs 14 and 15, which are provided with recesses 1'5 and I1 respectively to retain the inextensible cord hereinbefore described. It will be seen. that when said ,unit is substituted for one of the 'pin-pointunitsin the instrument, and the points B and l9 thereof aligned at an angle to the line-formed by the centre line of the leg and the other leg, an oval or similar-curviform figureg-vvill-be scribed. It is apparent that,1by :varyingthe distance between the pin points of said unit, andthe angle .at.:,which they are placed, variousoviformifigurescan be scribed. I

Inorder to scribe spirals an element as shown in Figure 1'7 is secured to one of the compass legs and is shown so secured in the fragmentary view in Figure I w i m r se a t m" lig emnea furnished with a. spirally'g r'ooved port on 8 1 extending from a platform furnished on'its lower Wound aboutfthespir 7 ide with. four points 83 and provided on its upper side with a hook 84. s V

The loop .of cord, .as shown in Figure, '18 is engaged inthe leg 1 and the loop ofcord 48 is lly grooved portion and secured to the hook '84 f M In the rotation of the device about the stem 80 the cord progressively 'unwinds'from the spiral groove and the'pen '43 in consequence progressively moves outward, thus scribing the spiral.

To scribe spirals of different pitches devices as shown in Figure 19 are used having grooved portions of different diameters- A'SLWiH be apprcciatedgwhen so used the leg 6 does not function, the pin Zlbeing withdrawn fromit. r

Preferably, in accordance with the invention thespreader or expansion spring arm 30 is made ingtwo sections, one of which will be furnished with .a hole by which'it may be engaged in position by the nut 12, the other end being furnished with a screw and nut and spaced apart from the screw and nut with a headed pin engaging in a slot provided in theptherportion of the spring arm so that the two sections may be relatively moved in increasing or decreasing the effective length of the spring arm as may be desirable or even necessary .to enable ellipses and other curves of widely different'dimensions to bescribed.

1. A drafting instrument for scribing a variety of curved figures, saidinstrument comprising a compass, a surface engaging "point having an annular channel therein fixed vto each leg of said compass, a ,cord surroundingsaid surface engaging points in contact with the annular channels therein, an S-shaped spring arm pivoted to said compass to swingthereabout and a scriber unit for scribing ,a curve about said compass carried by said spring arm and adjustable with respect thereto about a horizontal axis, said scriber unit havin an eye'therein through which a portion of said cord may pass, in combination with a winding pin rotatable -in said scriber unit to draw a portion of said cord through the eye in said scriber unit against the tension of said. spring arm to adjust the distance of said scriber unit from said surface engaging points.

2. A drafting instrument for scribing an ellipse, said instrument comprising a compass, a pin point unit pivotally. secured to the lower end of each compassleg, a surface engaging point having an annular channel therein fixed to each of said pin point units, acord surrounding said surface engaging points .in contact with 'the annular channels therein, a bracket collar vertically 'movableon said compass and pivotedto swing thereabout, an S-shaped spring arm fixed at one end to said bracket collar and extending downwardly and outwardly therefrom, and a scriber unit carriedby said spring arm for scribing a curve about said compass, said scriber unit having an eye therein through which a portion of said cord may pass, in combination with a'winding pin rotatable in said scriber unit to draw a portion of said cord through the eye in said scriber unit against the tension of said spring arm to adjust the distance of said scriber unit from said surface engaging points.

3. A drafting instrument for scribing a variety of curved figures, said instrumentcomprising a com-pass, an 'S-shaped spring armpivoted to said compass to swing completely thereabout, a scriber unit for-scribing acurve about said compass car ried by'said spring arm and-adjustable with respect thereto aboutahorizontaltaxis, and apord acorns extending between said scriber unit and said compass for limiting the position of said scriber unit with respect to said compass, in combination with replaceable surface engaging points detachably secured to said compass formed to determine the character of the curved figure to be scribed, one of said points being forked to provide two surface engaging units, said surface engaging points having channels therein to guide said cord.

4. A' drafting instrument for scribing a variety of curved figures, said instrument comprising a compass, an S-shaped spring arm pivoted to said compass to swing completely thereabout, a scriber unit for scribing a curve about said compass carried by said spring arm and adjustable with respect thereto about a horizontal axis, said scriber unit having an eye therein through which a cord may pass, a spirally grooved stem detachably connected to one leg of said compass, and a surface engaging platform having points on its lower face integral with said stem beyond its connection with said compass, 'in combination with a cord connected to said scriber unit and to said platform and Wound about said stem in the spiral groove'therein, and a winding pin rotatable in said scriber unit to draw a portion of said cord through the eyein said scriber unit against the tension of said spring arm to adjust the distance of said scriber unit from said surface engaging platform, whereby in swingingabout said compass said scriber unitwill unwind said cord from said stem and progressively increase its distance from said compass to scribea spiral.

5. A drafting instrument for scribing a variety of curved figures, said instrument comprising a compass, a surface engaging member having a circumferential channel therein fixed to a leg of said compass, a'cord surrounding said surface engaging member in contact with the channel therein, an S-shaped sprin arm pivoted to said compass toswing thereabout, and a scriber unit for scribing a curve about said compass carried by said spring arm and adjustable with respect thereto about a horizontal axis, said scriber unit having an eye therein through which a portion of said cord may pass, in combination with a winding pin rotatable in said scriber unit to draw a portion of said cord through the eye in said scriber unit'against the tension of said spring arm to adjust'the distance of said scriber unit from said surface engaging member.

6. A drafting instrument for scribing a variety of curved figures, said instrument comprising a compass, a surface engaging member having a circumferential channel therein fixed to a leg of said compass, a cord surrounding said surface engaging member in contact with the channel therein, a removable S-shaped spring arm pivoted to said compass toswing thereabout, and a scriber unit for scribing a curve about said compass'carried by said spring arm and adjustable with respect thereto about a horizontal axis, said scriber unit having an eye therein through which a portion of said cord may pass, in combination with a winding pin rotatable in said scriber'unit to draw a portion of said cord through the eye'in said scriber unit against the tension of said spring arm to adjust the distance of said scriber unit from said surface engaging member, said S-shaped spring arm being removable from said compass together with the elements carried thereby to permit use of said compass as such;

- VICTOR DEBS.

(References on following page) REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Schaefer Mar. 9, 1858 Hazard Dec. 30, 1884 Lundstrom Jan. 26, 1892 Davis Nov. 22, 1892 Griffith Nov. 10, 1903 Crowder Mar. 29, 1921 Number Number Name Date Hardt Oct. 10, 1922 Stossel Aug. 13, 1929 Ronning Aug. 16, 1932 Sommer 'Nov. 1, 1932 FOREIGN PATENTS Country Date Great Britain 1863 Germany July 26, 1887 Austria. Feb. 26, 1912 Germany July 11, 1936 

